GETYENT(3)             BSD Library Functions Manual             GETYENT(3)

NAME
     getttyent, getttynam, setttyent, endttyent -- get ttys file entry
     isdialuptty, isnettty -- determine tty type from ttys file entry

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     ##include <>

     struct ttyent *
     getttyent(void);

     struct ttyent *
     getttynam(const char *name);

     int
     setttyent(void);

     int
     endttyent(void);

     int
     isdialuptty(const char *name);

     int
     isnettty(const char *name);

DESCRIPTION
     The getttyent(), and getttynam() functions each return a pointer to an
     object, with the following structure, containing the broken-out fields of
     a line from the tty description file.

     struct ttyent {
             char    *tyname;       /* terminal device name */
             char    *tygetty;      /* command to execute, usually getty */
             char    *tytype;       /* terminal type for termcap */
     #define TYON          0x01    /* enable logins (start tygetty program) */
     #define TYSECURE      0x02    /* allow uid of 0 to login */
     #define TYDIALUP      0x04    /* is a dialup tty */
     #define TYNETWORK     0x08    /* is a network tty */
             int     tystatus;      /* status flags */
             char    *tywindow;     /* command to start up window manager */
             char    *tycomment;    /* comment field */
             char    *tygroup;      /* tty group name */
     };

     The fields are as follows:

     tyname     The name of the character-special file.

     tygetty    The name of the command invoked by init(8) to initialize tty
                 line characteristics.

     tytype     The name of the default terminal type connected to this tty
                 line.

     tystatus   A mask of bit fields which indicate various actions allowed
                 on this tty line.  The possible flags are as follows:

                 TYON       Enables logins (i.e., init(8) will start the
                              command referenced by tygetty on this entry).

                 TYSECURE   Allow users with a uid of 0 to login on this
                              terminal.

                 TYDIALUP   Identifies a tty as a dialin line.  If this flag
                              is set, then isdialuptty() will return a non-
                              zero value.

                 TYNETWORK  Identifies a tty used for network connections.
                              If this flag is set, then isnettty() will return
                              a non-zero value.

     tywindow   The command to execute for a window system associated with
                 the line.

     tygroup    A group name to which the tty belongs.  If no group is speci-
                 fied in the ttys description file, then the tty is placed in
                 an anonymous group called "none".

     tycomment  Any trailing comment field, with any leading hash marks
                 (``#'') or whitespace removed.

     If any of the fields pointing to character strings are unspecified, they
     are returned as null pointers.  The field tystatus will be zero if no
     flag values are specified.

     See ttys(5) for a more complete discussion of the meaning and usage of
     the fields.

     The getttyent() function reads the next line from the ttys file, opening
     the file if necessary.  The setttyent() function rewinds the file if
     open, or opens the file if it is unopened.  The endttyent() function
     closes any open files.

     The getttynam() function searches from the beginning of the file until a
     matching name is found (or until EOF is encountered).

RETURN VALUES
     The routines getttyent() and getttynam() return a null pointer on EOF or
     error.  The setttyent() function and endttyent() return 0 on failure and
     1 on success.

     The routines isdialuptty() and isnettty() return non-zero if the dialup
     or network flag is set for the tty entry relating to the tty named by the
     parameter, and zero otherwise.

FILES
     /etc/ttys

SEE ALSO
     login(1), ttyslot(3), gettytab(5), termcap(5), ttys(5), getty(8), init(8)

HISTORY
     The getttyent(), getttynam(), setttyent(), and endttyent() functions
     appeared in 4.3BSD.

BUGS
     These functions use static data storage; if the data is needed for future
     use, it should be copied before any subsequent calls overwrite it.

BSD                            November 17, 1996                           BSD